1977 700 Merc will not run.

[Ronsubsailor]

I've been working on this motor for several weeks now. I have ignition and fuel. Spark on all three cylinders yet the motor will not run. I have replaced most of the electronic parts. Rotor,trigger,coils,switchbox and rectifier.This moter has the CDM ignition system. I'm wondering if the timing is off so far that it will not run. I thought I had the wrong stator but checked all parts houses and they have the same number listed. The installation instruction say mount so wiring harness on the stator is starboard. Is mounting critical as it can be mounted in several positions? I have the repair manual but most of the tunning is done while the motor is running. Any suggestions will be appricated.

 

[Chris1956]

Re: 1977 700 Merc will not run.

Ron, A 1977 Merc 700 has the three coil, ADI ignition. It does not have a distributor and rotor, or CDM Ignition. You either have the wrong year or wrong nomenclature. The CDIElectronics website will have a troubleshooting procedure for your ignition system.

 

[ajgraz]

Re: 1977 700 Merc will not run.

Post serial number and we can be sure what year.

Stator has to be mounted a certain way just so all the wires can reach where they are supposed to.

Have you checked compression? When's the last time the carbs were cleaned? Does it fire at all?

 

[Ronsubsailor]

Re: 1977 700 Merc will not run.

You are correct. It has the CD ignition without points. Someone put CDM and I thought that was what it stood for. That's the reason I thought it may make a difference on mounting the Stator. So I should have used ADI. I have the CDI troubleshooting guide. That's how I determind some parts were bad. I have spark and fuel. Thanks,

 

[Ronsubsailor]

Re: 1977 700 Merc will not run.

Compression is over 100 (about 115)and balanced between cylinders. I haven't rebuilt the carbs yet but was wanting to make sure it fired up first. I've been spraying gas mix into the intake hoping it would at least fire up. I plan to order carb kits and water pump. Just thought it would at least fire up first. As you can see I've spent a lot on parts already. I have a 35hp. I could put on the boat. The wiring on the stator reach fine. Serial #471543 the title say's 1977. Thanks,

 

[merc850]

Re: 1977 700 Merc will not run.

Did you pull the flywheel or take it apart to replace the stator?
To check for timing remove all the plugs and put a pencil into the Nr. 1 cylinder then turn the flywheel until the piston has moved to the top of its stroke, this is TDC it should line up with a mark on the flywheel. Ground the plugs and turn the flywheel with the ignition on until you see and hear the 1 plug fire, this will give you an idea of the timing.

 

[Ronsubsailor]

Re: 1977 700 Merc will not run.

Yes, the flywheel was removed but it only lines up one way it has a wide spline that fits in the shaft. I turned the fly wheel to top dead center with a screwdriver in the spark plug hole on cylinder #1 to check it, moving the flywheel back and forth to verify TDC. Every thing was good. I will try for a spark. I think it should fire BFTDC. I'll check the specs. to see when. Thanks,